The present invention relates to an improved microprocessor controlled load bank. More particularly, the present invention relates to a load bank which is self-contained, compact and portable.
There has been a great need for a self-contained, compact and portable load bank for the testing of batteries and/or DC power supplies, and particularly DC power supplies utilized to recharge the batteries. Many systems today, and particularly large telephone systems utilize large batteries for emergency power in the case of a power failure. It is essential that the batteries be tested so that they can supply the necessary DC power during an emergency power outage, and particularly during an emergency power outage of extended duration. Without proper testing, and maintenance as a result of that testing, telephone companies and others that rely upon such emergency backup battery power have no way of knowing whether or not the batteries will function properly when an emergency occurs. Only by proper testing under controlled loads, with controlled current drain for a predetermined period, can the battery and each of its cells be effectively tested. It is only with such testing that any defective or unacceptably weak cells in the battery can be replaced or repaired, or other necessary repairs performed such as the correction of bad connections.
Battery analyzers utilizing load bank resistors controlled by a microprocessor are known, for example see U.S. Pat. No. 4,352,067-Ottone. However, self-contained, compact and portable load banks for such testing have not been available. Furthermore, fine control of load bank resistance that can maintain constant current has not been available.